Fuel pump for internal-combustion motors



J1me 1944- A. G.- F. WALLGREN ET AL 2,350,434 I FUEL PUMP FOR INTERNAL COMBUSTION MOTORS Filed Feb. 4, 1941 3 Sheets-Sheet l @D Q 2/ 8 6 0 0 U 35 3 LEJI-L Q June 5,1944 A. G. F. WALLGREN' ET AL 2,350,434

FUEL PUMP FOR INTERNAL COMBUSTION MOTORS J1me 1944- A; G. F. WALLGREN ETAL 2,350,434

' FUEL PUMP FOR INTERNAL COMBUSTION MOTORS s Sheets-Sheet 3 Filed Feb. 4, 1941 2 02 01 7356 y 4 c, M m/HTOENEY Patented June 6, 1944 NITED STATES PATENT OFFICE FUEL PUMP FOR. INTERNAL-COBBUSTION MOTORS August Gunnar FerdinandWallgi-en, Oscar Filip Holmstriim, and Kaleb Emil Evrell, Eskilstuna,

Sweden Application February 4, 1941, Serial No. 377,320

In Sweden December 21, 1939 '1 Claims.

trolling edge 21, and at the bottom by a control ling edge 28. Extending through the plunger 6 is a bore 1 communicating at the top with an annular recess 8 on the inside of the sleeve 9, and at the bottom with a recess provided in the plunger, said recess communicating with a bore 4 in the fixed member 9a. The opening of the .bore I is plugged against the space 25 underneath the plunger.

members channels and a recess are provided, said /m\with an intake 1 for the combustible oil through recess having a varying'axialextension around.

T atmospheric through the pump.

Further objects and advantages of the invention will be apparent from the following description considered in connection with.the accompanying drawings, which form a part of this specification, and of which:

Fig. 1 is a view partly in sectionof the upper part of a cylinder of an internal combustion motor with an injection apparatus according to the invention disposed in the cylinder cover of the motor;

Fig. 2 is a longitudinal section of the injectio apparatus on an enlarged scale;

Fig. 3 is a section taken on the line III-III of Fig. 2; I

Figs. 4, bands and '1 are longitudinal sections of the plunger and of a sleeve surrounding the same in diflerent positions of load.

In the drawings, 6 denotes a plunger which is I reciprocatable in a lining within an external casing 38. Said lining comprises two members, one

lower fixed member 9a which is screwed fast to a lower cap "a pertaining to the casing 38, and an upper. rotatable member .9, 9b, There is no axial force on the rotatable member 9, 9b originating from the plunger forces. The rotatable member is composed of an inner sleeve 9 and an outer sleeve 91), which latter is shrunk onto the inner sleeve 9 so as to be rotatably movable together with the same. The plunger 6 is provided between its end portions with a recess forming a space 23 with the inner sleeve 9, said space being bounded at the top by a spirally extending cona passage 3 provided in the casing 38. Extending through the plunger Bis another bore 24 which opens at the bottom in' the lower end sur- 26 and 29, respectively, in the sleeve 9. Diametrically opposite the recess 5, there is provided another recess 5a (see Fig. 3) in the plunger 6, which communicates with the bore [5 and, through a bore is provided in the fixed member 9a and a passage H in the casing 38, with an outlet for the combustible oil. v

All by-passes in the sleeve are, as will be evi-' dent from the aforesaid, .arranged either on the inside of the inner sleeve 9 or between the two sleeves 9, 9b, whereas the outer side of the external sleeve 91) is smooth. Between the outside of the sleeve 91) and the casing 38 there is a play 'large enough to prevent any contact.

The injection apparatus is mounted in the cylinder cover 40 in a jacket 39 which is well cooled by water, said jacket consisting preferably of copper or some other material of good heat-conductivity, the atomizer point 33 of the apparatus grojecting somewhat into the combustion chamer. bracket ll and a screw 42 against the conical seat 43 of the jacket 39 so as to provide a good tightening effect against the gas pressure prevailing within the combustion chamber.

Ifhe pressure chamber 25 of the pump communicates with the combustion chamber by means of a valve 30, a passage 3i, and a plurality of minuteapertures 32 arranged in the atomizer point 33; The valve 30 prevents leakage both of combustible oil into the combustion chamber The bore 4 communicates The casing 38 is pressed by means of a bring about a pressure as required for sufiicient atomization of the fuel.

The sleeve I is provided at the top with a pinion a engaged by a toothed rack is (see Fig. 1).

which is connected to a lever II, the position of which is controlled by a governor (not shown).

To prevent the plunger d from being carried along in the rotary movements of the sleeve I, to, the plunger is formed at the top with a part II of angular section which is guided in the easin! It.

The downward movement of the plunger (the pressure stroke) is effected positively by means of a cam disk ll through the agency of a rod II and a lever 2| bearing onthe upper end of the plunger. The upward return movement of the plunger is eifected by means of a spring 2 l which with its one end bears against the casing II and with its other end agdnst a sleeve 43 slidably mounted on the casing.

Fuel oil is supplied by a circulation pump under pressure of a few atmospheres, and enters, on

having preferably passed through a iilter, into the injection apparatus through the intake i. Thence the fuel passes through channel 3, bore l, recess I, bore I, annular space I and aperture II to the groove II. From the groove ii the fuel passes through aperture l2, space ll, aperture i4, bore ll, recess la, bore It. and passage II to the opening Fla. The intake l and the opening l'la communicate with one another in all positions of the plunger and form a constantly open pssage for recirculation of the fuel. B the fact that cold fuel always circulates in this manner through the apparatus, a uniform temperature will be obtained in all parts of the apparatus, besides which all traces of air will be eifectively removed from the system.

During the last portion of the return stroke of the plunger, the groove ll communicates with the chamber 2! through the port It, the space 28, the aperture 12, and the bore 24, the pressure chamber II and the appertaining passages being thus filled with fueh When during the pressure stroke the plunger moves downwardly under the influence of the linkage ll, 20, the cilia the chamber II will first be displaced through bore 24, aperture 12,

space ",andportllbacktothespace II and the plunger the oil is pressed out without resistance through said port, groove Ila, aperture Ila,

annular recess I3, and further, through the open passage of fiow. when during the upward return movement of the plunger as caused by the spring ii the upper edge 2-1 of the spiral-shaped space is uncovers the port It, the pressure chamber 2 again fills with fuel in the manner above described. I

The effective pressure stroke consequently lasts controlling edge 21 of the space 23 covers the port 28, to the moment at which the straight edge 28 of the space 23 uncovers the port I. Fig. 4 shows the apparatus as adjusted for full load. the length of the effective pressure stroke being then the greatest and equal to the distance a, inasmuch asthe port 28 is then covered already by the lowest part of the spiral-shaped controlling edge 21. By rotating the sleeve 0 in a counter-clockwise direction, viewed from above in Fig. 2 and Figs. t-l, under the influence of an impulse from the governor, the position of the port It will be altered relatively to the controlling edge 21 in amanner such that the port It is covered later and later. Fig. 5 shows the apparatus as adjusted for half-load operation. The sleeve 9 has been turned by 90 from the position shown in Fig. 4, and the eil'ective pump stroke has been reduced so as to correspond to the distance b. In Fig. 6, the apparatus .is adjusted for idle operations. The sleeve has been turned by 180, and the effective length of stroke has been reduced so as to correspond to the distance c. In 1'18. '1, the sleeve has. been turned by 270, and the effective length of stroke is naught.

The position of the plunger 8 in the plunger lining may be adjusted by means of an adjusting nut M on the upper end of the rod [9, the distance between the upper plane of the spring abutment II and the upper plane of the apparatus casing 3! being then adjusted to a predetermined value for each type of apparatus.

While we have described several more or less specific embodiments of our invention, it is to be understood that this has been done for purposes of illustration only and that our invention is not to be limited thereto, but its scope is to be determined by the appended claims viewed in the light of the prior art.

What we claim is:

1. A fuel pump for internal combustion engines comprising a rotatable sleeve member, and an axially movable plunger member in said sleeve member, means around one end of said plunger forming a pump chamber, said means being formed with a discharge injection outlet from said chamber, a fuel supply conduit comprising channels formed in the interior portions of said from the moment at which the spiral-shaped 18 members to prevent communication between the exterior of saidsleeve member and said conduit, a recess in one of said members having varying axial extent around the pump axis and a port in the other of said members in communication with said fuel conduit, and a passage formed in one of said members connecting said recess with said pump chamber, said port and said recess being located to be in communication in certain stroke positions of the plunger and to be out of communication with each other in other stroke positions of the plunger, whereby to determine the eifective stroke of the pump plunger and pro viding a variation in the length of the efiective stroke upon turning of said sleeve due to the varying axial extent of said recess.

2. A fuel pump for internal combustion engines comprising a rotatable sleeve member, and an axially movable plunger member in said sleeve member, means around one end of said plunger forming a pump chamber, said means being formed with a discharge injection outlet from said chamber. a fuel supply conliit comprising channels formed in the interior portions of said members to prevent communicatim between the exterior of said sleeve member and said conduit,

a recess'in' one of said members having varying axial extent around the pump axis and a port in the other of said members in communication with said fuel conduit, and apassage formed in one of said members connecting said recess with said pump chamber, said port and said recess being located to be in communication in certain stroke positions of the plunger and to be out of communication with each other in other stroke positions ofrthe plunger, whereby to determine the effective stroke of the pump plunger and providing a variation in the length of the effective stroke upon turning of said sleeve due to the varying axial extent of said recess and cooperating openings in said members having sufllcient axial extent so as to be in registry in all stroke positions of said plunger, and an outlet conduit for excess fuel, one of said cooperative openings being in communication with said supply conduit and the other cooperative opening being in communication with said outlet conduit.

3. A fuel pump for internal combustion engines comprising a rotatable sleeve member, and

an axially movable plunger member in saidsleeve member, means around one end of said plunger forming a pump chamber, said means being formed with a discharge injection outlet from said chamber, a fuel supply conduit comprising there being clearance between said rotatable sleeve and said housing. c

5. A fuel pump for internal combustion engines comprising a rotatable sleeve member, and

members'to prevent communication between the i exterior of said sleeve member and said conduit,

channels formed in the interior portions of said members to prevent communication between'the exterior of said sleeve member and said conduit,

a recess, in one of said members having varying axial extent around the pump axis and a port in the other of said members in communication with said fuel conduit, and a passage formed in one of said members connecting said recess with said pump chamber, said port and said recess being located to be in communication in certain stroke positions of the plunger and to be out of communication with each other in other stroke positions of the plunger, whereby to determine the effective stroke of the pum plunger and providing a variation in the length of the effective stroke upon turning of said sleeve due to the varying axial extent of said recess, said sleeve member comprising two concentric parts rigidly prising channels formed in said housing and in the interior portions of said members to prevent communication between the exterior of said sleeve member and said conduit, a recess in one of said members having varying axial extent around the pump axis and a port in the other of said members in. communication with said fuel conduit, and a passage formed in one of said members connecting said recess with said pump formedin said casing, a fuel supply conduit comchamber, said port and said recess being located to be in communication in certain stroke posi- :tions of the plunger and to be out of communication with each other in-other stroke positions of the plunger, whereby to determine the effective stroke of the plunger and providing a variation of the effective stroke uponturning of said sleeve due to the varying axial extent of said recess,

a recess in one of said members having varying axial extent around the pump axis and a port in the other of said members in communication with said fuel conduit, and a passage formed in one of said members connecting said recess with said pump chamber, said port and said recess being located to be in communication in certain stroke positions of the plunger and to be out of communication with each other in other stroke positions of the plunger, whereby to determine the effective stroke of the pump plunger and providing a variation inathe length of the effec tive stroke upon turning 'of said sleeve due to the varying axial extent of said recess, said port being formed in the inner part of said sleeve member and communicating with a channel between said parts, and an outlet conduit for excess fuel, said channel between the parts being permanently in communication with said fuel supply conduit and with said outlet conduit.

6. A fuel pump for internal combustion engines comprising a rotatable sleeve member, and an axially movableplunger member in said sleeve member, means around one end of said plunger forming a pump chamber, said' means being formed with a discharge injection outlet from said chamber, a fuel supply conduit comprising channels formed in the interior portions of said members to prevent communication between the exterior of said sleeve member and said conduit, a recess in one of said members having varying axial extent around the pump axis and a port in the other of said membersin communication with said fuel conduit, and a'passage formed in one of said members connecting said recess with said pump chamber, said port and said recess being located to be in communication in certain stroke positions ofthe plunger and to be out of communication with each other in other stroke positions of the plunger, whereby to determine the effective stroke of the pump plunger and providing a variation in the length of the effective stroke upon turning of said sleeve, due to the varying axial extent of said recess, said sleeve member comprising two concentric parts rigidly secured together, the channels in the sleeve member being formed in the inner part and between said parts and the outer surface of said outer part being smooth, said port being formed in the ,inner part of said sleeve member and communicating with a first channel between said parts, an outlet conduit for excess fuel, said first channel between the parts being permanently in communication with said fuel supply conduit and zwith said outlet conduit, and a second port in the inner part of said sleeve communicating with a second channel between said parts, said second poi-t being located so as to communicate with ,said recess at the end of the pressure stroke, said second channel being permanently in communication with said outlet conduit.

7. Ina fuel pump for internal combustion engines, a pump casing, means at one end of said casing providing a bore and a compression chamber, said means being formed with a discharge injection outlet from said chamber, a plunger reciprocably mounted in said bore, a sleeve rotatably mounted around said plunger within said casing in axial alignment with said means, a first port in said means communicating with an inlet passage in said housing, a second port in said plunger, the location and axial extents of said ports being such that they communicate with each other in all positions of said plunger, a channel in said plunger communicating with said second port and with a third port in said plunger, said sleeve being formed with a first annular recess so located and dimensioned as to communicate with said third port in all positions 0! said plunger and said sleeve, said sleeve having an axially extending passage communicating with said first recess and with a second annular recess in said sleeve, a fourth port in said plunger, said second recess and said fourth port being so located and dimensioned as to be in communication in all positions of said plunger and said sleeve, an axial passage in said plunger connecting said fourth port with a flith port in said plunger, a sixth port in said means communicating with an overflow passage in said casing, said fifth and sixth ports being so located and dimensioned as to be in communication in all positions of said plunger, a recess in said plunger having varying axial extent around the pump axis, a seventh port in said sleeve communicating with the axial passage therethrough and being so located with respect to said recess in the plunger as to be in communication therewith in only certain stroke positions, whereby to determine the elective stroke oi the plunger and providing a variation of the effective stroke upon turning of said sleeve due to the varying axial extent oi. the

recess in the plunger, a passage in said plunger connecting the last-mentioned recess with said compression chamber, an eighth port in said sleeve so located and dimensioned as to communicate with the recess in the plunger at the end of the eflectivestroke, and a passage in said sleeve connecting said eighth port with said second annular recess in the sleeve, the space between said sleeve and said casing being out oi communication with all of said passages, recesses and ports whereby fuel is prevented from entering said space.

AUGUST QUNNAR FERDI- NAND WALLGREN. oscaa m1? nonms'rabm. KALEB EMIL EVRELL. 

